Wallet signature to deterministic KDF for public-private keypair
About the feasibility and security implications of a scheme I'm trying to do for my project, it will make use of proxy re-encryption, end to end, which would essentially need public/private keypairs. The approach involves having a crypto wallet (e.g. Metamask) sign a static / non-changing message, let's say from a server, to generate a signature after a user confirms to sign the signature. This signature will then be subject to a deterministic key derivation function (involves curve ordering to generate a valid private key) to derive said public/private keypairs to be used. Means the private key must always be the same since the user needs to re-derive the keys to encrypt/decrypt data and be used for proxy re-encryption. Note that this key mgmt. function only happens at client side, and store in-memory. The generated signature or private/public keypairs are never sent anywhere.
